package collection;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;

public class CollectionDemo2 {
    public static void main(String[] args) {
        //Collection c = new ArrayList();
        Collection c = new HashSet();
        c.add(new Point(1,2));
        c.add(new Point(2,2));
        c.add(new Point(3,4));
        c.add(new Point(5,6));
        c.add(new Point(7,8));
        c.add(new Point(9,10));
        Point p = new Point(1,2);
        c.add(new Point(1,2));//重复元素无法放入Set集合两次
        System.out.println(c.contains(p));
        System.out.println(c);

        c.remove(p);
        System.out.println(c);
    }
}
